The story
- Proto-Indo-European*teg-
- Proto-Indo-European*tégus
- Proto-Germanic*þekuz
- Proto-West Germanic*þikkwī
- Old Englishþicce
- Old Englishþiccet
- Middle English*thikket
- English todaythicket
Inherited from Middle English *thikket, from Old English þiccet, from þicce (“thick”) + Old English nominal suffix -et. Compare similar German Dickicht (“thicket”), which is first attested in the 17th century, however. Compare typologically Bulgarian гъстак (găstak), Macedonian густеж (gustež), Czech houští, Polish gęstwina (< *gǫstъ); Latin dūmus (akin to Latin dense).
Etymology from Wiktionary, CC BY-SA 4.0.